Ever since the Supreme Court gave states permission to opt out of Obamacare's Medicaid expansion, a number of Republican governors have declined to participate under the pretense that it would be wildly expensive. This hardy band of resistors includes Texas's Rick Perry, whose state has the highest fraction of uninsured residents in the country, as well as Florida's Rick Scott, Louisiana's Bobby Jindal, and South Carolina's Nikki Haley, whose states are all tied for fourth on that list. Their justification has always sounded a bit dubious, since the federal government has promised to fund 93 percent of the expansion for a decade, and at least 90 percent of it after that.